1. Field of the Invention
The preset invention relates to an arrangement unit for an umbilical member arranged at a robot arm section of an industrial robot.
2. Description of the Related Art
When an industrial robot is used for an operation, the robot is required to be provided with an umbilical member including a cable for transmitting power or a signal and/or a tube for transmitting coolant or activation gas to a hand or a welding gun attached to the end of a wrist section of the robot, via a forearm of the robot. It is necessary that the umbilical member, arranged around the forearm of the robot, has a certain amount of extra length (margin) so that excess force is not applied to the umbilical member while the rotation of the forearm. On the other hand, the extra length of the umbilical member may be slack depending on the position and/or the orientation of the forearm of the robot, and the umbilical is required to not interfere with external equipment, such as a neighboring robot, a hand, a jig, workpiece, etc.
For example, Japanese Unexamined Patent Publication No. 2003-136462 discloses a guide member for avoiding interference due to extra length of an umbilical member. Concretely, it is described that guide member 15 is a cylindrical member arranged coaxially with an upper arm 1, and configured to cover a welding cable 7 wound around upper arm 1 so that welding cable 7 is retained within an annular space between upper arm 1 and guide member 15.
In the configuration of Japanese Unexamined Patent Publication No. 2003-136462, the umbilical member is restrained by the guide member. Therefore, excess force may be applied to the restrained portion of the umbilical member, and thus the durability of the umbilical member may be affected. Further, when the umbilical member is replaced with another, removing and attaching operations of the umbilical member relative to the guide member must be carried out, such operations are troublesome for an operator.